Alarm mechanism



Patented Apr. 1, 1924.

unirse srnrss ANDRU G. PAPPADAKIS, OF DETROIT, MICHIGAN.

ALARM MECHANISM.

Application filed February 26, 1923. Serial No. 621,328.

T0 all whom it may conce/m.'

lle it known that I, ANDRU G. PArrADAiiis, a citizen of the UnitedStates, residing at Detroit, in the county of Wayne and State ofMichigan, have invented certain new and useful Improvements in AlarmMechanisms, of which the following is a specification, reference beinghad to the accompanying drawings.

This invention relates toalarm mechanisms and it is one of the objectsthereof to provide a mechanism that will sound an alarm when the doorknob is rotated, and to provide means whereby this mechanism may bedisconnected so that the knob may rotate without sounding the alarm ifdesired. y

Among other aims and objects of the invention may be recited theprovision of a device of the character mentioned, with a View tocompactness, and in which the number of parts are few, the constructionsimple7 the cost of production small, and efficiency and operation high.

The improvements in the details and arrangement of parts will beapparent from an inspection of the accompanying drawings, in connectionwith the description hereinafter contained, and wherein a preferredembodiment of the invention is disclosed for the purpose of imparting anunderstanding of the same.

In the drawings, wherein like characters of reference indicatecorresponding parts in the several views;

Figure 1 is an elevation of my improved device with a portion of themechanism broken away; and

Figure 2 is a fragmentary plan view thereof.

Referring to the drawings, 10 designates a portion of the door, 11 theescutcheon plate upon one-side thereof, 12 the escutcheon plate upon theopposite side, 13 the knob spindle which is substantially7 rectangularin cross section, as is usual, although not necessarily limited to suchshape, 14 and 15 the door knobs, and 16 the latch shown herein as havingtwo bars 17 connected therewith and tail pieces 18 upon the inner endsthereof.

The latch is normally moved outwardly by the coil springs 19, whichsurround the bars 17 and at their inner ends abut against a plate 2Oheld against movement in one direction by the lugs 21, usually integralwith the lock case.

My invention contemplates the use of a bell 22 or similar device, whichis shown herein as mounted upon a plate 23 slidably mounted within thelugs 24 fixed to either one of the escutcheon plates, as shown in thedrawings,.and within a recess 25 in the door 10, or it may be mounted inthe lock or latch case with which the knob spindle is connected, or inany other convenient manner.

The bell 22 is of a conventional type and requires no furtherdescription herein, being operated through a pinion 26 mounted upon aspindle 27 journaled in the plate 23 and having a gear 28 which meshesinto a pinion 29 on the post supporting the bell. All of this mechanism,that is, the bell and the pinion, gear, etc., are mounted upon the plate23 so as to be moved as a unit therewith by means of the button 30 thatpasses through a slot 31 in the escutcheon plate 12 and fixed at itsinner end to the plate 23. A plate 32 associated with the but-ton 30conceals the slot 31 irrespective of theposition of the button 30relative thereto.

The latch 16 is drawn in manually in the usual manner by means of thehub 33 mounted upon the spindle 13, the fingers 34 thereon engaging thetail piece 18 for that purpose. This latch, and the mechanism foractuating the same, is only one of many forms that are in use andconstitutes no part of my present invention.

Connected with the hub 33 is a sector 35,

the teeth of which mesh into those of the pinion 26 when the latter ismoved into operative position through the manipulation of the button 30.wWhen so engaged the pinion 18 is actuated through the sector 35 so thatrotation of the knobs 14 and 15 even to a very limited degree impartsrotarv movement to the sector 35 and through it the bell mechanism isactuated, thus sounding the alarm.

If it is not desired that an alarm should be sounded the plate 23 andall of its associated mechanism, through the manipulation of the button30, is moved so that the teeth of thefpinio'n are out of engagement withthose of the sector 35, thus the ating the alarm mechanism. ln someknol) mechanisms one of the knobs may be rotated without in'ipartingmotion to the other, in which case the sector 35 may be directlyassociated with either one of them, so that the rotation of one knobonly will sound the alarm. The plate 23 is held in its extreme positionby the spring` 3G that is secured at one end by a screw 37 and whichenters either one of the notches 38 and 39 depending upon the relativeposition of the plate. The springv engages the notch 38 When the alarmmechanism is in position to be sounded by the rotation of the knob andthe notch 39 when it is out of the path of movement of the sector Thereare minor changes and alterations that may be made Within my invention,and I would therefore have it understood that I do not limit lmyself tothe exact construction herein described, but claim all that falls fairlywithin the. spirit and scope of the appended claim.

Having described my invention, what I claim as new and desire to secureby Letters Patent, is

In a device of the character described, the combination With anescutcheon plate having` a plurality of lugs upon the inside thereof; aplate slidably mounted between said lugs; an alarm mechanism connectedWith the inside of said plate so as to be moved therewith, the source ofpower for operation thereof being through a pinion; a knob spindlerotatably mounted in said escutcheon plate; a sector on said spindle;and means exterior to said escutcheon plate having connection with saidplate for moving the same toward and away from said spindle and saidpinion into and out of engagement with said sector plate.

In testimony whereof, l have hereunto aiiixed my signature.

ANDRU G. PAPPADAKIS.

